Blame view

readline/src/pad/prac1/EditableBufferedReader.java 5.16 KB
Imanol-Mikel Barba Sabariego authored
1
2
3
4
5
6
package pad.prac1;
import java.io.*;


public class EditableBufferedReader extends BufferedReader 
{
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
	/*
	 * MODE DEFINITIONS
	 */

	public static final int INSERT = 0;
	public static final int OVERWRITE = 1;
	public static final int DEL_BACKWARD = 0;
	public static final int DEL_FORWARD = 1;

	/*
	 * TYPE DEFINITIONS
	 */

	public static final int ESCAPE_SEQUENCE = 0;
	public static final int PRINTABLE = 1;
	public static final int NON_PRINTABLE = 2;

	/* KEY DEFINITIONS
	 * ESC (0x1B) starts an escape sequence
	 * ESC+[+C (0x1B 0x5B 0x43) Cursor Forward
	 * ESC+[+D (0x1B 0x5B 0x44) Cursor Backward
	 * ESC+[+2+~ (0x1B 0x5B 0x32 0x7E) Insert
	 * ESC+[+3+~ (0x1B 0x5B 0x33 0x7E) Delete forward
	 * ESC+O+H (0x1B 0x4F 0x48) Home
	 * ESC+O+F (0x1B 0x4F 0x46) End
	 */

	public static final int RETURN_KEY 		= 0x0D;
	public static final int BACKSPACE 		= 0x08;
	public static final int BACKSPACE_DEL 	= 0x7B;
	public static final int ESC 			= 0x1B;
	public static final int ESC_SEQ 		= 0x5B;
	public static final int FORWARD_C 		= 0x43;
	public static final int BACKWARD_D		= 0x44;
	public static final int DEL_3 			= 0x33;
	public static final int TILDE 			= 0x7E;
	public static final int HOME_END 		= 0x4F;
	public static final int HOME 			= 0x48;
	public static final int END 			= 0x46;
	public static final int INSERT_2		= 0x32;
Imanol-Mikel Barba Sabariego authored
48
	private String line = "";
49
50
	private int lineLength = 0;
	private int cursorPosition = 1;
Imanol-Mikel Barba Sabariego authored
51
	private boolean returnKey = false;
52
53
	private int writeMode = INSERT;
Imanol-Mikel Barba Sabariego authored
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76

	public EditableBufferedReader(Reader in)
	{
		super(in);
	}

	public EditableBufferedReader(Reader in, int sz)
	{
		super(in,sz);
	}

	private void setRaw() throws IOException, InterruptedException
	{
		String[] cmd = {"/bin/sh", "-c", "stty raw -echo </dev/tty"};
		Runtime.getRuntime().exec(cmd).waitFor();
	}

	private void unsetRaw() throws IOException, InterruptedException
	{
		String[] cmd = {"/bin/sh", "-c", "stty -raw echo </dev/tty"};
		Runtime.getRuntime().exec(cmd).waitFor();
	}
77
78
	private int parseKey(int key)
	{
79
		//TO IMPLEMENT BOTH MODES
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
		return PRINTABLE;
	}

	public void addChar(char character)
	{
		//switch writemode
		//if insert
			//print space
			//moveto cursorPosition-1
			//print char
			//add to string
			//update string length
			//update cursor position
		//if overwrite
			//just print char
			//add to string
			//update string length
			//update cursor position
	}

	public void delChar(int mode)
	{
		//switch mode
		//if back
			//del char using backspace
			//remove char from line string
			//update cursor position
			//update line length
		//if forward
			//moveto cursorPosition+1
			//del char using backspace
			//remove char from line string
			//update line length
	}

	private void moveCursorForward()
	{
		System.out.print((char)ESC);
		System.out.print((char)ESC_SEQ);
		System.out.print((char)FORWARD_C);
	}

	private void moveCursorBackward()
	{
		System.out.print((char)ESC);
		System.out.print((char)ESC_SEQ);
		System.out.print((char)BACKWARD_D);
	}

	public void moveCursorTo(int pos)
	{
		if((pos <= lineLength) && (pos >= 1))
		{
			if(pos > cursorPosition)
			{
				for(int i = 0; i < (pos - cursorPosition); i++)
				{
					moveCursorForward();
				}
			}

			else if(pos < cursorPosition)
			{
				for(int i = 0; i < (cursorPosition - pos); i++)
				{
					moveCursorBackward();
				}
			}
			cursorPosition = pos;
		}
	}
Imanol-Mikel Barba Sabariego authored
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
	public int read() throws IOException
	{
		return super.read();
	}

	public String readLine()
	{
		try 
		{
			setRaw();
		} 
		catch (Exception e) 
		{
			System.out.println("Couldn't set terminal in raw mode");
			return "";
		}
		while(!returnKey)
		{
			try 
			{
				int character = read();
173
174
				System.out.println("\n\n" + character + "\n");
				switch(parseKey(character))
Imanol-Mikel Barba Sabariego authored
175
				{
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
					case ESCAPE_SEQUENCE:
						if(read() == ESC_SEQ)
						{
							switch(read())
							{
								case FORWARD_C:
									moveCursorTo(cursorPosition+1);
									break;

								case BACKWARD_D:
									moveCursorTo(cursorPosition-1);
									break;

								case DEL_3:
									if(read() == TILDE)
									{
										delChar(DEL_FORWARD);
									}
									break;

								case INSERT_2:
									if(read() == TILDE)
									{
										writeMode = 1-writeMode;
									}
									break;

								case HOME_END:
									switch(read())
									{
										case HOME:
											moveCursorTo(1);
											break;

										case END:
											moveCursorTo(lineLength+1);
											break;
									}
									break;
							}
						}
						break;

					case PRINTABLE:
						switch(character)
						{
							case RETURN_KEY:
								returnKey = true;
								break;

							case BACKSPACE:
							case BACKSPACE_DEL:
								delChar(DEL_BACKWARD);
								break;

							default:
								addChar((char)character);
								break;
						}
Imanol-Mikel Barba Sabariego authored
235
						break;
236
237
238

					case NON_PRINTABLE:
						//ignore
Imanol-Mikel Barba Sabariego authored
239
240
						break;
				}
241
Imanol-Mikel Barba Sabariego authored
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
			} 
			catch (IOException e)
			{
				System.out.println("Couldn't unset raw mode");
				break;
			}
		}
		try 
		{
			unsetRaw();
		} 
		catch (Exception e) 
		{
			System.out.println("Couldn't unset raw mode");
			return "";
		}
258
		System.out.println("");
Imanol-Mikel Barba Sabariego authored
259
260
261
		return line;
	}
}